Step 1: Match each item based on biological relevance.
\begin{itemize}
\item A. Specimens are preserved in a place, typically associated with a location — here, linked to III. Howrah, which is where the Indian Botanical Garden is located.
\item B. Indian Botanical Garden is located in III. Howrah.
\item C. Manuals provide a collection of species — linked to I. Names of species in an area.
\item D. Monographs are detailed accounts of a single taxon — matched with IV. Information of one taxon.
\end{itemize}